Method of and system for reproducing sounds



April 7, 1931. H. KUCHENMEISTER 1,799,378

METHOD OF AND SYSTEM FOR REPRODUCING SOUNDS Filed Sept. 15, 1926 2 Sheets-Sheet 1 k Hllll'llllll nnpnuiuununnnununnu' 4 HHIIII UUDDDIJDDUUUUUDEIDUD 3 lllHlllHll a a a 1 2 9 12% 2 1 nnw'ununnuun 11 H X nunnnnuuunuonun 10 H019 hunununuuu nnunuununnuuu uu '23 DDUDOUDUIJ 43 Fig.6

I I 46 INVENTUR e/a nu'el enmupz METHOD OF AND SYSTEM FOR REPRODUCING SOUNDS Filed Sept. 15, 1926 2 Sheets-Sheet 2 w Fig.7.

Attorney.

Patented Apr; 7, 1931 v UNITED STATES PATENT OFFICE HEINRICH KU'GEENMEISTEB, OF BERLIN, GERMANY METHOD OF AND SYSTEM FOR REPRODUCING SOUNDS Application filed September. 15, 1926 Serial No. 135,650, and in Germany September 22, 1925.

Myinvention relates to improvements in the method of and system for reprdducing sounds,the sound records used in the system, and the method of making the said records.

5 More particularly my invention relates to the system in which a plurality of impulses are producedat slightly spaced oints of the sound record. The object of t e improvements is to provide a method and a s stem by means of which the sounds reprod uced b elongated records can be improved in ua photo-cellgthe electrical resistance of which is varied y means of oscillating light rays and which reproduces electrical currents actuating a suitable sound receiver. Further, the improved method maybe used in connection with records in the form of steel wire magnetized so as to represent a sound record. In order to improve the uality of the sound reproduced by means 0 sound records of this type, I produce a pluralityof sound waves of different phase.

For the purpose of explaining the invention, several examples embodying the same have been shown in the accompanying drawings, in which the same letters of reference have been used in all the views to indicate corresponding parts. In said drawings:

40 Fig. 1 is a diagrammatic view showing a film band provided with an o 'tical diapositive and a plurality of soun records displaced with relation to each other in longitudinal direction,

Fig. 2 is a diagrammatic view showin the method of producing a plurality o "gourd records of 'difierent phase on a film Fig. 3 is a similar view showing a modification,

Fig. 4 is a similar view showing another modification in which a plurality of microphones are located at difi'erent distances from the source of sounds, and in which sound records different in phase are produced on the film, v Fig. 5 is a diagrammatic perspective view showing) the manner of reproducing the sounds y means of a film band having similar records synchronously provided thereon,

Fig. 6 is a similar perspective view showing the method of reproducin means of a single sound recor and reproducing apparatuses acting on spaced parts of the record,

Fig. 7 is a diagrammatic view showing the method of reproducing sounds by means of a single record and a single reproducing apparatus, the said reproducing apparatus being connected with loud speaking receivers disposed at difierent points of the film theatre, 1

Fig. 8 is a dia rammatic view illustrating a method in which sound impulses are pro.- duced by means of a source of light. acting on different points of a single record, and

Fig. 9 shows a modification in which elec trical waves of difierent phase are produced from a sound record and transformed into sounds by means of a single receiver.

In Fig. 1 I have shown a film 1.f0r kinematographic reproduction provided in the usual way with fields 2 containing the succession series of optical images. In addition, the film band is provided with a sound record 3 provided thereon by optical means in the manner to be described hereafter. In addition to the sound record 3 a sound record 4 or 5 is provided on the film band, and the said records tor 5 are dis laced'with relation to the record 3 longitu 'nally of the film band, as has been indicated by heavy-and light shading of the sound records 3, 4 and 5, the phase difi'erence a of the said records being about 1/30 to 1/8 of a second.

In Fig. 21 have illustrated one way of pro sounds by ducing sound records of different base on the film band. In the saidifigure t e source of sounds 6 acts on two micro hopes 7'and 8 electrically connected within nsifiers 9 and 10. The said intensifiers are connected by leads 11 with apparatuses 12 and 13 for exposing the film, which apparatuses consist for example, of incandescent lamps, galvanometers carrylng mirrors, or the'like. By means of the said apparatuses the film is exposed Fig. 2.

- ters. The microphones 21 and 22 are con-.

"according to the sound oscillations. As shown, the exposing apparatuses 12 and 13 are disposed with relation to each other longitudinally of-the film, the distance'a between the said apparatuses corresponding to a hase difference of 1/30 to 1/8 of a second.

11 Fig. 3 I have shown a modification of the apparatus for producing the sound records, in which the source of sounds 14 acts on a single microphone 15 connected by leads 16 including an intensifier 17 with two exposing apparatuses 18'and 19 displaced with relation to each other longitudinally of the film. Also in this case, similar sound records are producedon the film, which however differ in phase,* i n a similar way as shown in In the modification shown in Fig. 4 the source of sounds 20 acts on two microphones, or other sound transforming apparatuses, 21 and'22 located at different distances from the said source. For .example, the distance be- .tween the source 20 and the microphone 21 is one meter, while the distance betweenthe said source and the microphone 22 is 31 menected byleads 23 and 24 including intensifiers 25 with two exposing apparatuses 26 and 27 disposed one beside the other. The

sound waves reach the microphone 22 later I so In another modification method," sound records of different phase are produced on the film by making thereon two copies of the negative, one beside the other, the negative being slightly shifted longitudinally of the film when; making the second copy.

In Figs. 5 to 9, I have illustrated t e method of reproducing the series of sounds recorded on the film. In the embodiment shown in Fig. 5, a film 30 is used in which two sound records 31 and 32 are synchronously disposed one beside'the other, and separate reproducing means are provided for each record. As shown each re roducing apparatus comprises a source 0 light rays 33, 34 adapted to direct the rays through the film records 31, 32 and onto a photo-cellv (llliot shown), the electrical resistance of whic is varied in dependence on the variation'of the intensi of the light pxisdiiithrough the records. e'

said cells are connected by leads 35 including intensifiers 36, 37 with loud speakers 38 and 39. Inorder to reproduce the sounds of the records at the desired phase difference, the sources of light 33 and 34 and the photo-cells are displaced with relation to each other iongitudinally of the film, as is indicated In Fig. 6 I have shown a modification in which the film 40 is provided with a single sound record 41. For reproducing the sounds, two sources of-light 42 and 43 and cooperating photo-cells (not shown) are provided each of which photo-cells is connected with intensifiers 44, 45 and loud speakers 46, 47. The sources of light 42, 43 and photo-cells are displayed with relation to each other longitudinally of the film, as is indicated by a4.

In Fig. 7 I have shown a modification in which the film is likewise provided with a single sound record. For reproducing the sounds, a single source of light 51 is provided,

the rays of which are divided by suitable means, such as a Nicol prism 52, into two branches 53, 54 each of which acts on a photocell 55,56 connected by leads 57, 58 with intensifiers 59, 60 and loud speakers 61, 62 The latter are disposed within the theatre atdifl'erent distances from the seats of the hear- 'ers. By the reproducing apparatus sounds of equal phase are produced by the loud speakers 61 and 62, but the latter being disposed. at different distances from the hearers the sounds reach the ears of the hearers ,in immediatesuccession one after the other, so that the timbre is improved. 4

In Fig. 8 I have shown a modification in which a single record'is provided on the film 65, and in which the rays emanating from a single'source of light .66 are divided by a Nicol prism 67 into two branches 68 and 69 passing through the sound record at slightly spaced points thereof and acting on photocells 70 and 71. The photo-cells are connected by leads 72, 73 with intensifiers 74, 75 and loud speakers 76 and 78. In this modification, the phase difi'erence is produced by causing the branches 68 and 69 of the pencil of lightto pass through spaced port-ions of the sound record.

Finally, in the modification shown in Fig. 9 the film 80 is provided with two sound records 81 and 82 having difi'erent phases. The sources of light 83 84 act on separate photo-cells (not shown; connected with a common intensifier 85 and the same loud speakers 86. In the operation of the system the soundim ulses. of diiferent phases are superposedwmhin the loud speaker86. In

lieu of thefsingle loud speaker a group of loud speakersmay be provided, whereby'the intens ty and colour of the sound are mater ailllly improved.

the above description 'of the invention reference has been made to elongated sound records adapted to vary the light passing through the same. But I wish it to be understood that m invention is not limited to this feature, an that it generally relates to sound'records, provided on elongated carriers, such for example as carriers consisting of steel wires or bands magnetized according to p the character of the sounds and reproducing 9. art.

the said sounds in the manner known in the By means of reproducing apparatus of this type, the intensity and colour of the sounds are improved in the same way as has been described above by reproducing thev sounds at a suitable phase difference.

Practically a phase difierence of from 1/30 to 1/10 of a second was found to ive the best results. But I have found t at even 'a smaller phase difierence will cause an a preciable improvement of the colour 0 the sounds.

1. The method of improving the tone quality in talking films, which consists in producing in the film through optical means a plurality of phase-displaced sound 'record.

lmpressions, with a time interval of from 1/8 to 1/30 of a second and converting said impressions into sound. 30

2.v The method of improving the tone quality in talking films, which consists in producing in the film a plurality of phase-displaced sound record impressions by a single recording means, comprising a plurality of devices for optically producing the impressions on the film, while acting at different places longitudinally of the film, with a time interval of from 1/8 to 1/30 of a second and converting said impressions into sound.

3. The method of improving the tone qual ity in talking films, which consists in producing in the film through optical means a plurality of phase-displaced sound record impressions, and converting said impressions into sound by means of a single sound reproducin device excited a plurality of times at a pre etermined time interval.

In testimony whereof I hereunto aflix my signature.

HEINRICH KUCHENMEISTER. 

